Prize Winning Cheese Soup

This is the soup recipe that I made on Good Things Utah and won the runner up prize with. It is all done in the microwave. It is filling and delicious. We always have soups for dinner on Christmas Eve. This one is a tradition. It's nice to do in the microwave and free up the stove for other things.

4 cups cubed potatoes (3-4 potatoes), raw
2 cups carrots (2-3 carrots), cut diagonally
1 pkg frozen broccoli, thawed
1/2 cup margarine
2 cups milk
2 cups chopped celery
1 cup chopped onion
3 cups water
6 chicken bouillon cubes
1 Tbsp dry mustard
2 lbs(1Pkg)processed American Cheese (Velveeta), cubed
1/2 cup flour
2 tsp black pepper

Microwave:
Combine water, celery, onion, carrots, and potatoes in a 4 quart casserole dish. Cook on HIGH 15 min. until the vegetables are crisp, tender.
Stir in broccoli, bouillon, margarine, dry mustard, pepper, and Velveeta.
In a small bowl mix milk and flour. Add milk mixture slowly to the cheese and vegetable mixture and stir well. Cook on MED HIGH (70%) 20 min. until the vegetables are done.
Serves 12